Cannula



' F. C. ATWOOD Nov. 1924.

CIANNULA fi'-'ad Jan. 12

FIG. 1

FIG. 2

Patentecl Nov. 4, 1924.'

UNITED STATES PATENT QEEICE.

FRANCIS CLARKE ATW'OOD, 0F NEW'TON, MASS'kCHUSETTS, ASSIGNOR, BY MESNE AS- SIGNMENTS, 'I'O AMERICAN PROTEIN CORPORATION, 0F BOSTON, MASSACHUSETTS,

.A CORPORATION 0F MASSACHUSETTS.

GANNULA.

Application filed January 12, 1921.

To all 'ui/'tom it may concern:

Be it known that I, FRANCIS CLARKE Arwoon, a citizen of the United States of America, and resident of Newton, in the county of Middlesex and State of Massachusetts, have invented new and useful lmprovements in Cannulas, of which the following is a specification.

This invention relatcs to a cannula especially designed for collecting blood from food animals at the time of slaughter in oondition suitable for human food or for therapeutic purposes. An essential condition for accomplishing this, assuming the health of the animal, is that the blood be drawn from the interior of the body of the animal without coming in contact with the exterior of the animal or with any other contaminating influence. The principal object of the present invention is to provide a novel and improved form of cannula which may be readily inserted in a previously made incision in the body of the animal without carrying in contaminating matter with it, which will permit the blood to flow freely therethrough from the interior1 of the body, and which may be firmly retained in the incision while the blood is flowing.

In the accompanying drawings which illustrate a preferred embodiment of the invention,

Figure l is a plan view of the forward end of the instrument; and

Figure 2 is a side elevation, partly in longitudinal central section;

The cannula comprises the tubular body 1, which may be of any convenient length, and is designed to be connected at its lower or rear end with a suitable tube or pipe (not shown) running to a container. At the forward end of the tube l is a head of openwork construction which has a tapered or converging forward end and a rearward part presenting salient or projecting por- Scriall No. 436,644.

of ribs 4 bowed outwardly beyond the periphcry of the tubular body, and thence curving inwardly to form a forwardly converging, tapering and pointed end The openwork construction thus formed is adapted easily to slip into a previously formed cut or incision by reason of its tapered form, and to spread the lips of the cut apart by reason of its outwardly bowed or projecting portions, thus facilitating the entrance of the end of the tubular body 1.

.and preventing it from catching on the lips of the incision and carrying containinating matter :into the cut.

Then the end of the tubular body and the head are inserted in the cut the openwork construction of the. head. permits the blood to flow freely therethrough into the tube. rl`he lips of the cut tend to close around. the end of the tube and the enlarged or laterally projecting parts of the head aid in holding the instrument in place. If desired a clamping or gripping device of the character forming' the subject matter of another application filed concurrently herewith may be used to clamp the lips of the cut around the end of the tube below the projecting portions of the head, thus firmly securing the instrument in the incision and tightly closing the lips of the cut around the tube while the blood is being' drained off.

I claim:

l. A cannula having a hollow body to provide a conduit surmounted by a head of openworlr construction consisting of a plurality of circumferentially spaced ribs bowed outwardly beyond the hollow body and terminating at the upper portion of the head in a tapering pointed end.

2. A cannula having` a hollow body to provide a substantially unobstructed conduit, a skeleton openwork head surmounting the body and comprising a plurality of ribs diverging outwardly from the upper portion of the body and thence converging to a tapered upper end.

signed by me at Boston, Massachusetts, 'this seventh day of January, 1921.

FRANCIS CLARKE ATWOOD. 

